Yup. Robot vacuum cleaner! That was the first project Chen Jin planned on doing for his start-up business. In fact, he had already decided to develop robot vacuum cleaners like Wa-Wah on Earth a long time ago. He would then sell the robot vacuums to thousands of families, saving the housewives from doing endless house chores. A very promising market prospect indeed!
The truth was, it didn't require advanced technology to build robot vacuum cleaners; there was already a great number of products like that on Earth, forming a fairly mature market. But it was just civil technology, nothing high tech.
So Chen Jin chose to start with the industry that had relatively "easier requirements," and launch the "killer robot vacuum" that was capable of keeping the floor sparkly clean with much better cleaning features, leaving the rest of the robot vacuums in the dust.